Fundamentals of Heat and Mass Transfer
7th Edition
ISBN: 9780470501979
Author: Frank P. Incropera, David P. DeWitt, Theodore L. Bergman, Adrienne S. Lavine
Publisher: Wiley, John & Sons, Incorporated
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Chapter 1, Problem 1.29P
Under conditions for which the same room temperatureis maintained by a heating or cooling system, it is not uncommonfor a person to feel chilled in the winter but comfortable in the summer. Provide a plausible explanation for this situation (with supporting calculations)by considering a room whose air temperature is maintained at 20°C throughout the year, while the walls ofthe room are nominally at 27°C and 14°C in the summer and winter, respectively. The exposed surface of aperson in the room may be assumed to be at a temperature of 32°C throughout the year and to have an emissivity of 0.90. The coefficient associated with heattransfer by natural convection between the person andthe room air is approximately
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Chapter 1 Solutions
Fundamentals of Heat and Mass Transfer
Ch. 1 - The thermal conductivity of a sheet of rigid,...Ch. 1 - The heat flux that is applied to the left face of...Ch. 1 - A concrete wall, which has a surface area of 20m2...Ch. 1 - The concrete slab of a basement is 11 in long. 8...Ch. 1 - Consider Figure 1.3. The heat flux in the...Ch. 1 - The heal flux through a wood slab 50 mm thick,...Ch. 1 - The inner and outer surface temperatures of a...Ch. 1 - A thermodynamic analysis of a proposed Brayton...Ch. 1 - A glass window of width W=1m and height H=2m is 5...Ch. 1 - A freezer compartment consists of a cubical cavity...
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